Method for the separation of aluminum nitrate from potassium, sodium, iron, calcium,magnesium nitrates, present in mixed solutions of these salts



Patented Feb. 16, 1932 UNETEDSTATES PATENT OFFICE GIAN ALBERTO BLANG, or norm, ITALY METHOD FOR THE SEPARATION OI ALUMINUM NITRAT'E FROM POTASSIUM, SODIUM,-

men, CALCIUM, MAGNESIUM NITRATES, rnnsnnr IN MIXED SOLUTIONS ormnnsn SALTS No Drawing. Application filed January 15, 1926,

vMy invention relates to a method of separating aluminum nitrate from potassium, sodium, iron, calcium, magnesium nitrates, present inmixed solutions of these salts.

The patent application. No. 508,807 of October 19, 1921, describes a method of separating aluminum chloride from potassium chloride, iron chloride and the like present in mixed solutionsof these salts such as are obtained, for example, by treating leucite with hydrochloric acid.

This method is based on the propertyof aluminum chloride of being practically insoluble in suiilciently concentrated solutions of hydrochloric acid, whereas chlorides of po- 6070% in nitric acid has been reached.

These highlyconcentrated mixtures of nitrates having a slight excess of nitric acid are obtained by the action of nitric acid on minerals consisting of alu-minumand potassium, or of aluminum and calcium, sodium, magnesium, which generally also contain iron as an impurity. When as a result of such action, the mixed solution of aluminum nitrate and of one or more nitrates. of the other above-mentioned elements is obtained, it is sufficient to increase the acidity of the solution by the addition of nitric acid in order to initiate a crystallization which is more or lesscomplete according to the degree of acidity-of the aluminum nitrate, thefotherni- Serial No. 81,590, and in Italy January 28, 1925.

Whilst t potassium and iron nitrates remain in solution. a

Iclaim:

The method of separating aluminum nitrate from the'mixed solutions of nitrates obtained by the treatment of minerals, e. g.

leucite'and the like, containing aluminum in y conjunction with other alkali metals or alkalinefearth metals, which consists in adding 7 to the solution concentrated nitric acid, thereby increasing itsacidity to such a point that the entirealu'minum nitrate will crystallize. In testimony whereof I have afiixed my signature [this 31st day of December, 1925. i r GIAN ALBERTO BLANC.

completely effected when a concentration of.

trates remaining insolution. In particular,

in the case of leucite (potassium-aluminum silicate containing iron as'impurlty) aluminum nitrateis obtained by crystallization, r 

